Now that the mri picked up a meniscus root displacement on a mri after surgery does that ean i need surgery again to repair the displacement?

Not always: Mri is very sensitive to meniscus disease and can show changes in the tissue even when you have no symptoms. However, if you are experiencing pain or clicking with pain or inability to bend your knee well with this MRI finding, you may consider arthroscopy.

See below: I am not an orthopedic surgeon but my understanding is that meniscal root repair is not simple. It's not like the simple debridement of some other types of meniscal tear. That being said meniscal root tear is significant, causing an unstable meniscus, particularly if it's the medial meniscus. Surgery, however, depends not only on MRI but also your symptoms and expectations.